sapphire screen

When we think of sapphires, most of us think of the expensive gemstones used in jewelry, but many people do not know sapphires actually have had a wide variety of industrial applications for hundreds of years. Why would companies want to use such an expensive mineral in their technology products? First and foremost, sapphire is incredibly durable, behind only diamond as the second hardest mineral, scoring 9.0 out of 10 on the Mohs scale of mineral hardness. It is also a very chemically stable mineral. Sapphire’s durability and chemical stability has made it ideal for use in precision mechanics, timepieces, displays and more, across many different industries.

Real sapphire – which is a variety of the mineral corundum, an aluminum oxide – saw its first industrial application more than 300 years ago as jewel bearings in high-end mechanical timepieces. While this was costly, longevity and accuracy were worth the high price of these components. These types of timepieces were built to pass down from generation to generation.

The first man-made sapphire was produced as far back as 1902, using a process of grinding natural aluminum oxide into powder and then heating it to 3,761°F. While most sapphires used in jewelry are colored, this is actually due to impurities in the mineral. Without any impurities present, sapphire is a completely clear material. It has high strength, anti-abrasion and anti-corrosion characteristics, good light transmission, and can be processed into sheets, all of which are ideal for clear device displays, such as smartphones, watches, microwaves, projectors, as well as precision tools and other electronic components.

Kyocera has been producing and utilizing man-made single-crystal sapphire for electronic components for more than 40 years. Some of the uses for sapphire include watch lenses, inspection equipment parts, medical diagnostic equipment parts and chamber windows. More recently, Kyocera began developing pure sapphire displays for its leading portfolio of ruggedized smartphones. Perfectly suited for rugged devices, sapphire displays have proven to be incredibly resistant to scratches and damage that often blemish smartphones. Once reserved for luxury phones costing thousands of dollars, only in the past few years have smartphone manufacturers begun using sapphire displays in mass-market phones, and Kyocera was the first.

Resisting ongoing, minor scratches and micro-fractures. When you pay hundreds of dollars for a smartphone, you don’t want the touchscreen display to be degraded and ruined over time by ugly scratches and cracks. As phones sit in pockets and purses, however, that’s exactly what happens when they get scraped by keys, coins and other hard objects. At Kyocera, we like to show off the durability of our Sapphire Shield display by testing it with steel wool, knives, coins and other common display-killers.

Enhancing the long-term integrity of the display. Think of how glass is typically cut. Rather than actually cutting all the way through a sheet of glass, traditional glass cutters simply score the glass so it can be broken along that same score. Similarly, scratches and micro-fractures in a phone display weaken its integrity over time by preparing it to be more easily broken along those fault lines.

Sapphire displays cost more than typical hardened-glass displays, which explains why they were historically used only in high-end luxury phones. Kyocera, however, has gotten past that issue and used sapphire displays in devices costing far less than today’s most popular smartphones. It’s a win-win for everyone involved, but especially for the phones’ users, who can worry less about cosmetic blemishing and long-term failure (i.e., shattering) of their displays.

John Chier is director of corporate communications at Kyocera. He has worked on the Kyocera team shaping its communications strategy over the past 15 years – 13 of those years in-house and two with a Kyocera agency partner. John has always had a passion for writing and began his career as a newspaper reporter at the Whittier Daily News, part of a multi-paper syndicate in Los Angeles. When not working, he and his wife can usually be found coaching, shuttling, refereeing or cheering for his three sons and their numerous plays.